As shown in FIG. 19, a conventional body section imaging apparatus 201 includes a gantry 203 having a cylindrical opening 202 for inserting a patient M, the opening 202 having a central axis 202a extending horizontally, a bed device 205 having a top board 204 for supporting the patient M in a supine position, and a top board moving mechanism 207 for moving the top board 204 vertically and horizontally. The body section imaging apparatus 201 having such construction may be a PET (Positron Emission Tomography) apparatus, for example.
The PET apparatus includes a multilayer detector ring 213 having detector rings in multiple layers with radiation detectors arranged in a ring form around the opening 202 of the gantry 203. Data is collected by carrying out coincidence counting with the multilayer detector ring 213 of two radial rays (e.g. gamma rays) released in 180° opposite directions from a patient medicated with a radioactive drug. A sectional image is acquired from image reconstruction of the collected data (see Patent Document 1, for example).
In such body section imaging apparatus 201, an operation for placing the patient M on the bed device 205, inserting, for example, the head of the patient M into the opening 202 of the gantry 203, and making positional adjustment to an imaging position is generally carried out as follows. That is, first, as shown in FIG. 19, the top board 204 of the bed device 205 is lowered vertically, and the patient M is seated on the top board 204 having been lowered to a low position. Then, as shown in FIG. 20, the patient M seated on the top board 204 is made to take a supine position. As shown in FIG. 21, the top board 204 with the patient M placed in the supine position thereon is raised vertically to an imaging height position. As shown in FIG. 22, the top board 204 raised to the imaging height position with the patient M placed thereon is moved horizontally to insert the head of the patient M into the opening 202 of the gantry 203, and positional adjustment is made to an effective field of view of the multilayer detector ring.
As this type of apparatus, apparatus have been disclosed which include a gantry body and a bed device capable of picking up images of a supine position and a seated position (see Patent Documents 2 and 3, for example).
In the apparatus disclosed in Patent Document 2, the gantry body is rotatably supported through support rods projecting from upper opposite ends thereof by a support frame. And, the gantry body is constructed to be rotatable and fixable to a predetermined inclination angle by a drive device using the support rods as fulcrum. On the other hand, the bed device has a reclining mechanism to be capable of setting a patient to a supine position or a seated position. The bed device has a lift device for vertically movably supporting a bed body, and a horizontally moving device which can move back and forth along guide rails. That is, the bed body is constructed movable vertically and horizontally.
In the apparatus disclosed in Patent Document 3, the gantry body is rotatably supported by a lift member through a tilt rod (support rod). The tilt rod has a sector connecting gear fixed thereto. The connecting gear is constructed to receive power from a drive mechanism through a gear mechanism which moves a lift member vertically. That is, the gantry body is movable up and down with the lift member, and the gantry body is constructed tiltable by the connecting gear rotating with ascent of the lift member. An examination table (bed device) is constructed movable vertically and horizontally.
[Patent Document 1]
Unexamined Patent Publication No. 2009-236726
[Patent Document 2]
Unexamined Patent Publication H6-14913
[Patent Document 3]
Unexamined Patent Publication H10-314160